Sulphur and nitrogen dual-doped mesoporous carbon hybrid coupling with graphite coated cobalt and cobalt sulfide nanoparticles: Rational synthesis and advanced multifunctional electrochemical properties

Doping-type carbon matrixes not only play a vital role on their electrochemical properties , but also are capable of suppressing the crush and aggregation phenomenon in the electrode reaction process for pristine metallic compound . Herein, graphite coated cobalt and cobalt sulfide nanoparticles decorating on sulphur and nitrogen dual-doped mesoporous carbon (Co@Co 9 S 8 /S- N -C) was fabricated by a combined hydrothermal reaction with pyrolysis method. Benefited from g-C 3 N 4 template and original synthetic route, as-obtained Co@Co 9 S 8 /S- N -C possessed high specific surface area (751.7   m 2   g −1 ), large pore volume (1.304   cm 3   g −1 ), S and N dual-doped component and relative integrated graphite skeleton, as results it was developed as decent oxygen reduction electro-catalyst and ultra-long-life Li-ion battery anode. Surprisingly, compared with commercial Pt/C, it displayed a higher half-wave potential (0.015   V positive) and lower Tafel slop (66   mV   s −1 ), indicating its superior ORR activities. Moreover, the ultra-long-life cyclic performances were revealed for lithium ion battery, exhibiting the retention capacities of 652.1   mAh   g −1 after 610 cycles at 0.2   A   g −1 , 432.1 and 405.7   mAh   g −1 at 5 and 10   A   g −1 after 1000 cycles, respectively. We propose that the synergistic effect of structure and chemical component superiorities should be responsible for the remarkable electrochemical behaviors of the Co@Co 9 S 8 /S- N -C.